A partir do Oracle 10g R2 a resposta é sim, existe uma ordenação obrigatória entre os itens em item_list_1 e item_list_2, mesmo que as definições do cursor sejam permitidas fora do lugar.
Por exemplo, uma definição de procedimento não é permitida antes de uma declaração de variável:
SQL> select * from v$version;
BANNER
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Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi
PL/SQL Release 10.2.0.4.0 - Production
CORE 10.2.0.4.0 Production
TNS for Solaris: Version 10.2.0.4.0 - Production
NLSRTL Version 10.2.0.4.0 - Production
SQL> declare
2 variable_declaration number;
3 procedure procedure_definition is begin
4 null;
5 end procedure_definition;
6 begin
7 null;
8 end;
9 /
PL/SQL procedure successfully completed.
SQL> declare
2 procedure procedure_definition is begin
3 null;
4 end procedure_definition;
5 variable_declaration number;
6 begin
7 null;
8 end;
9 /
variable_declaration number;
*
ERROR at line 5:
ORA-06550: line 5, column 5:
PLS-00103: Encountered the symbol "VARIABLE_DECLARATION" when expecting one of the following:
begin function package pragma procedure form
ORA-06550: line 8, column 4:
PLS-00103: Encountered the symbol "end-of-file" when expecting one of the following:
end not pragma final instantiable order overriding static
member constructor map
